Using anthracite in a Energy King Combo Wood/Coal Hot Air Furnace

Hello
I have a large output Energyking combo wood/coal add-on or stand alone hotair furnace.
I have used it for 2 years and am happy with it except for when the temp outside is above 20. Unless you want to add wood every 2 to 3 hours (one stick at a time) you will driven outside because it works way to well. This is hooked directly to hot air ducting with proper sized cold air returns and cross flow baffles and works in conjunction with oil . This is all fine .
I have air intake shut as far down as I can get it and use only 2 to 3 year seasoned wood or I would have had a major chimney fire by now . I guess the main problem the unit is just too efficient with wood fire. I have a 28 foot 6 inch SS insulated all fuel chimney. There is no barometric control installed( was told not a good idea if burning wood and chimney catches fire as it would create a super fire in pipe with the added air(this made sense to me). I was told with coal I need to have a chimney installed draft air regulator which is ok as I could block it if I used wood . I have baffles in grates that need to be switched to COAL so air is from bottom instead of top for wood.
My question is can I safely control a coal fire by restricting air intake as long as chimney is always at full flow with only a flapper type barometic draft control? Some call it an offset pin damper. Was told I must have this to allow fumes to always have a way up chimney.
Will I be able to control this fire better than with wood? I wll buy anthricite from a local dealer by ther bag to try it. He has given me his take on coal and he burns a stove in his home and a huge one in his shop and a smaller "round oak" stove.
What size coal should I start with? Pea or Chesnut? My furnace has shaker grates for coal and holds either 90 or 120 pounds of coal.
M<y deal;er thionks I shold have much more control of heat output with coal . Is this so?
Soory so long winded all advice appreciated. PS this is a hand feed unit . Was told only need to add coal every 2 days at very slow burn rate. Thank You I hope I can learn something I may not know yet.
Also am afraid of coal because I know a family that had a stove explode and killed 2 of there children years ago but many oldtimers swear by coal. I have burned wood for 40 years . Thanks TJV Sorry about the typos bad cut on my finger bandage is in way hits extra keys.

I have a hand fired furnace like yours. Let me tell you if you want heat, you need to fill the furnace with coal. I burned hard coal, and loaded close to 90 pounds. Its a bear to deal with at first, but its constant btus. I havent tried to burn coal yet in 30 to 50 degree weather. I was told to use my forced draft, which when the house calls for heat the coal will burn hotter, then die down when the house is warm. I remember the 1 night I woke up, it was almost 0 out, and I was rolling in sweat. The house was around 80 degrees, and hotter upstairs. It takes some time to get a good coal fire going, at least an hour. Put a thin layer over hot wood coals and open your bottom door a little to ignite the coal, then all another thin layer. Once you get a good coal be, pile it on and close the door. DO NOT OPEN The door to check it, give it about 30 minutes to burn some of the gas off, otherwise you will get a mini explosion, I have done it. Once its burning good, then turn it down where you want it. Close your feed door damper, and just open the draft under the fire. Once its burning, it will be fairly hard to put it out. From there you control the heat. I had probably a 15 to 16 hour burn, then I would add close to 35 pounds on top after shaking it down. I have a barometric damper and a key damper and I burn both wood and coal. The secret is check your chimney and flue pipe. I clean my flue once a month with my chimeny whether I need it or not.
I burned nut coal.

Thank You laynes.
My main draft is run by the thermostat and if its off little 2x2 intake is closed. The feed door draft is a large screwnut which is supposed to sustain constant air flow I am sure just like your furnace. I hope coal is the answer to a more controlable heat.
I am going to purchase a few bags of coal (chesnut) and try the coal in my furnace as soon as it stays below 40 during the day. I think the coal should be a lot less to fuss with than the wood.
Thanks for the info .....Just what I have been looking for ! tjv

If you find you can't control the nut try pea or mixture of both.

tjv wrote: Also am afraid of coal because I know a family that had a stove explode and killed 2 of there children years ago but many oldtimers swear by coal.

Coal is as safe as using any other unit providing you do the proper maintenance. I'd suggest it's safer, certainly safer than wood as you don't have the possibility of chimney fire to contend with. As I pointed out in another thread you don't have bomb sitting next to your house neither...

Good Luck tjv. Let me know how you make out with it. I burn mostly wood, but I like the coal heat in the dead of winter on a chilly night.

Hello tjv,
When you get a good coal fire going you will have more control over the heat output of your furnace, but you will still have a fire going, and the heat has to go somewhere, so if it isn't that cold outside, you may still have the house too hot. This is the 'problem' with hot air furnaces, they make heat that has to be circulated to the house or the furnace overheats.

With a boiler, the hot water can be used at lower settings, [~140*] and still have the ability to store excess heat [the water can get hotter ~200*] without the house having to get overly warm. Most boiler systems have some sort of 'heat-dump' system to prevent boiling the water. It is very difficult to make a heat-dump for a hot air system.

I think you will like coal, it will take some getting-used-to though. You should be able to control the heat output better than with wood. You said you planned on adding a draft damper [offset pin] this will be needed to keep a constant draft on the firebox, and your thermostat controlling the under-grate air intake. The combination of these should give you better control of your heat output.

You will have to shake the grates less often in warm weather and more often during cold weather to keep control of the air getting up through the ash on the grate. And of course empty the ash drawer.

Let us know how the coal is working, Greg

Hi Folks!
Still waiting for mother nature to drop the temps a little.
Been near 70 here all week long...But we know 30 n 40's are not far away now...Keep you posted as to how I make out with coal . Thanks tjv